Ridley and Mercatali developed a working relationship upon discovering their overlapping theatrical tastes and – crucially, Mercatali adds – turn offs. Nearly a decade after meeting, they chat with me in the same bare room their latest joint project Radiant Vermin rehearsed all day in, displaying such understanding of each other through their slickly interweaving answers that I wonder whether they prepared a script just for me. But, with the Radiant Vermin premiere fast-approaching, I know they have no time for that.

“Radiant Vermin is a comedy, about an hour and a half long with a couple of songs in – and that’s all I’m going to say!” responds Ridley to my unsubtle probing. Frustrating journalists is not the goal – or at least not the main goal – of Ridley and Mercatali’s evasiveness: they say that much of Radiant Vermin is currently even a secret from themselves and, as a result, they are scared of misleading me. Ignorance strikes me as an odd thing for a writer and director to admit about their own production, until both men launch into an explanation how crucial the audience is to live theatre.

“I’ve done the same stage play that one night looks like the biggest slapstick comedy and, the next, the biggest tragedy”, says Ridley. “You don’t know what you’ve got until you put a play in front of an audience. The meaning of the play can change over a run when something happens in the news or the weather is different. It is a sponge that soaks up everything.” Mercatali elaborates: “No audience reaction is better or worse than any other. It’s always brilliant, always a great tapestry to remember. The audience is like an animal. They work together and are encouraged by each other.”

Ridley and Mercatali have chosen trusted actors to shape the dynamic audience interaction that is particularly important in Radiant Vermin. Though they tend to cast new blood, recasting Gemma Whelan and Sean Verey from their joint works Dark Vanilla Jungle and Moonfleece respectively, as well as Amanda Daniels from Ridley’s Shivered, was an obvious choice: “there is a rhythm, a music to the writing you can’t go against”, Mercatali explains. “The actors get that. They are all as passionate about it as we are.”

Steering the conversations back to details about Radiant Vermin is impossible against the duo’s tide of passion for theatre and each other. Above all else, they value honesty and are nauseated by theatre that uses – as Mercatali puts it – “camouflage to covering what’s missing”. Radiant Vermin was inspired from Ridley’s observations of consumerism and obsession when he moved house during particularly high house prices last year. Everything he writes, he says, “is to an extent an exorcism of something that bothers me. In that way, my work always comes from a deep, honest place.”

Throughout their years together, Ridley and Mercatali have shared the key principle of prioritising the play over their ego. “We haven’t had any shouting matches”, says Ridley. “Not yet anyway…” Ridley is the first to pick up the pen to edit his script and Mercatali believes that “not being defensive is probably the biggest advice I can give to anybody in any relationship. If we listen to each other, take in what each other is saying and trust each other, the play is going to be what we want it to. You come to rely on the person to do what you can’t. It’s the best feeling in the world. If Phil likes what I’m doing, I feel bulletproof.”

“Is comedy not somewhat oxymoronic for you guys?” a friend asked them. After past productions featuring monologues and ensemble casts, love stories and far-right activists, and all with overarching themes of darkness, no one can pin the duo down. An hour interview has brought me no closer than being able to guarantee three things: Radiant Vermin will be attended by dedicated followers and unsuspecting newcomers alike; offer challenges, surprises and honesty; and is a play absolutely loved its two creators, Ridley and Mercatali.

Radiant Verminis playing at Tobacco Factory Theatre until 7 March and Soho Theatre until 12 April. Click on the link for more information and tickets.

Mimi is a recent graduate and aspiring journalist. When not searching for (and sometimes even undertaking) work experience, she spends time reading, writing and eating. She also really quite enjoys seeing theatre for free with AYT.